June 24, 2016

“My objection to the no-fly no-buy proposal, while certainly based on Second Amendment grounds, is more broadly one of opposition to any system that allows almost entirely unaccountable bureaucrats to restrict constitutional rights without notice, recourse, or accountability. No matter how meritorious you believe your cause to be, excising rights at the behest of a government executive or agency should terrify any right-thinking person. If you think the terror watch list is merely an affront to the Second Amendment, you’re not paying attention.

It doesn’t take a lot of effort to create a gedankenexpriment where the erosion of rights embodied in the Fourth and Fifth Amendments is the next stop on turning the Constitution into a Chinese menu where one party removes rights from Column A and the other from Column B. Just saying, ‘But guns…’ doesn’t make it less dangerous.”

June 18, 2016

Tig welded up battery box #2 today. Complete success! I did some quick and dirty JB weld spots to hold the loose pieces together while I did the tack welds. Unfortunately, the JB melted in spectacular fiery fashion (complete with noxious fumes). Good thing we have vent hoods. Ick.

I did some fast reclamping and got the tack welds in. From that stressful step on, though, it was smooth sailing. Kind of contemplative and relatively easy. I also laid one bead down that looks as good as anything I’ve seen on the pro welding sites. For that 6″ I was a Weld Master. The rest of it wasn’t as pretty but will still do the job.

Also, I managed to get the hang of vertical welds! That’s huge as up to now I’ve had to figure out a way to position everything horizontally. Still not good at them but they’re not catastrophic fails.

So that makes all three ankles, both shoulder horseshoes, both legs, and both battery boxes welded up! Now I have to do the three feet over the next week or so. After that will come the grinding. Oh… the grinding. I’ll be at that for a long time. After the grinding I’ll have to go touch up some welds, but all the parts should look seamless.

June 10, 2016

“America’s new fervor for socialism frightens me. To be sure, the United States in 2016 is a world apart from Venezuela in 1998. Our economy is much more vibrant, even in its current weak state. America also has a stronger tradition of innovation, intellectual inquiry and individualism, all of which have initially lessened the impact of our creeping socialism’s many problems.

But those problems ultimately derive from human nature itself, and human nature knows no borders. In fact, the steady growth of America’s welfare state and government interventionism — different from that in Venezuela in degree, but not in kind — shows that this country is far from immune.

The concept of wealth redistribution is already widely accepted in America, and its popularity has only grown with time. Both economic and personal liberties have declined with the regulatory state’s advance, weakening the nation’s ability to continue its historically unprecedented march of material progress. Special interests and cronies, meanwhile, have become amazingly adept at using the apparatus of government to enrich themselves at others’ expense.

My home country shows where this leads. So do other nations that have tried — and failed — to turn socialist dreams into reality. Like millions of Americans today, I used to have those dreams. I came to the United States after they turned into a nightmare. It frightens me to think what will happen as socialism becomes more popular here. Where else is there to go?”

Major progress the last few days and I even got a decent little injury to show for it (more on that later).

I’ve been practicing my TIG welding for around 40 hours and decided to just go ahead and give the leg welding a try. Before I did that, though, I had to strip the old anodizing from the parts. I’d gotten the 1/4″ metal for free when I had the frame anodized black. The only downside was that the two sheets of free metal were clear anodized, and since you can’t weld anodized metal I had to strip the parts in a concentrated lye bath.

First a 10 minute dip in the hot lye solution, constantly agitating each part while the anodizing was dissolved (but not too long or the aluminum will be eaten away!), followed by a neutralizing bath in vinegar, then a water rinse/soak, then pressure washing each part to remove residue. At the end of this 4 hour process all the clear anodizing was gone.

I doubled up on protective gear. Lye is nasty stuff.

Then into the welding bay! It took me 5 hours to set up and tack all of the parts in the first leg just on one side of the leg. A tack weld is when you just do a quick spot weld in a few places to hold the parts together firmly– once they’re tacked you then go back over and run beads that hold everything together. Tack welds are a pain because everything wants to shift and slide around and it’s hard getting all of the loose parts to behave until they’re secured. And at the tolerances I’m dealing with I have to get them all positioned as close to perfect as I can.

This took me five hours to tack weld just one side. I was holding the torch sideways (a hard angle), I kept dipping my tungsten rod in the molten aluminum (necessitating regrinding of the tungsten), and just generally going glacially slow. It sucked. It was very frustrating. I felt like I’d forgotten everything I’ve learned about welding. It was a frustrating session.

But then yesterday I went back in and tacked the other side of the leg on and then ran beads. They weren’t the prettiest welds I’ve ever done, but once I got the aluminum hot it welded pretty well. Success! Felt great. No, it felt fantastic. Erin brought home some ice cream in celebration. Yum.

Seven and a half hours…. for one leg!

Tonight I went back in to Techshop and set everything back up again. It generally takes me an hour to get the TIG bay ready to rock. I had to grind the edges of the 2nd leg parts, clean them with Alumiprep 33, rinse with water, scrub with a stainless brush to remove the remaining oxides, and then clean with acetone a final time.

Grinding:

You have to have aluminum as surgically clean as possible, with zero oxidation, before it’ll weld correctly. Any contamination and things go south very fast. I decided to clamp everything together tonight before I tack welded and it went much faster. I was able to tack weld around the perimeter of the whole piece in about an hour and a half, then remove the clamps and run beads in a couple of hours. All told, I finished the second leg in just about 5 hours. Much faster

And something funny happened a few hours into welding. Suddenly all of this practice I’ve been doing the last few weeks just…. clicked. When TIG welding, you have to control the torch angle and speed with your right hand, the distance of the tungsten rod to the surface (around 1/16th inch separation is really hard to hold), the angle and speed of the aluminum rod you’re dipping into the molten pool with your left hand, and the torch power with your foot. It’s a lot to keep track of and if you change one of the factors then the equation alters and the weld pool does weird things. Tonight I was like Daniel-san after waxing on/off Mr. Miagi’s car for hours. Suddenly it just got a lot easier and I was like Neo in the Matrix watching the bullets come down the hallway. It was weird and fun and exciting. As a result I put down some of my best weld beads I’ve ever done. I could watch the puddle form and actually control where it was going. Things were predictable and I had a more subconscious sense of what to do when things went a little wrong. It was like that feeling when, after months on training wheels, you take them off and your body just “knows” how to balance on a bike. I’m sure I got great weld penetration down into the metal and everything cooperated. I got it, and it was a blast.

One funny thing happened, though, when a glob of molten aluminum dropped free from the leg and disappeared between the slats of the table down toward the floor. Hmm… hope that doesn’t hit anything important. I then smelled burning fabric for a few seconds, then nothing. So I kept on welding. Later I noticed a 3/4″ long scar right in the top of my new Zamberlain leather hiking boot! So my right boot toe has a brand from R2. It’s not very noticeable and didn’t do any structural damage and kinda makes me smile when I look at it. That mark has a story. Kind of like the scars you get on an adventure: some you love for the stories they tell. No biggie.

The worse one today was when I was finishing up a weld and used my left hand (the one holding the super hot aluminum dipping rod) to raise my welding hood. Unfortunately, the rod got caught on the mask, popped up under my hood, and smacked me right in the upper lip.

While semi-molten.

So now my upper lip has a nice little burn mark and blister right smack dab in the middle at the very top. The lower lip got hit as well but didn’t get burned as badly. I hollered and hopped around for a minute, ran some cold water on it, and then hit it with some burn cream with 2% lidocaine. It’s numb right now and will take several days to heal and probably won’t scar. The joke around the R2 builder’s board online is that R2 requires a blood sacrifice every so often. Guess it was time. Working with 160 amps and 12,000 degree plasma, though…. it could have been much worse.

So anyway, the leg welds are done! I’ll need to spend a day or two grinding them down, but this is a huge step that I’ve been stressing about for over a year. I never thought I’d be able to learn TIG welding and seriously considered jobbing it out. I’m really glad I stuck it out and did it myself. So satisfying.

Next step is the foot assemblies and then the battery boxes. There’s still a lot of welding in my future. Once all that is done I’ll grind everything down (I am not looking forward to that day…those days) and then back fill any minor holes with Lab Metal, then sand it to a decent finish. I’ll still be throwing the legs on the mill for various operations (tapping, some more drilling, etc), so I won’t go crazy on the finish work until they’re all done.

Still, a really good week, in spite of the sartorial and facial scars. I’m really proud of what I’ve done.

June 1, 2016

I spent another 4 hours at the TIG welder today (for a total of 34 hours) and did my first solo TIG part! I did one of the outer ankles and it took me the whole time.

Once I got all set up and ready I took the ankle layers into the machine shop and used the 90 degree jig and a flat plate to stack the parts so that they lined up exactly. One of the issues I discovered on the center ankle that I did with Keith last week was that I rushed the setup and the ankle is now just barely skewed. It’ll still fit its mounting bracket but I have to persuade it slightly. No big deal since the part that’s off is up inside next to the frame where you can’t see it. The outer ankles are much more visible so it was more important that I get those just right.

Once the layers were aligned and clamped tightly I brushed them with the stainless wire brush and then some acetone to get them perfectly clean, then I hit them with 150 amps of TIG POWER! Since the parts were room temperature, and since aluminum is such an incredible heat sink (ever wonder why your pans are aluminum?), I had to concentrate all of that power into a few spots for almost four minutes before the part heated up enough to start puddling. That part got hot. Unfortunately, the Lincoln 225 TIG machine I’m using is rated at a 40% duty cycle, and after about six minutes it went into overheat shutdown mode.

Whoops.

So I had to wait almost 10 minutes for the machine to cool down before I could continue welding. Fortunately, the ankle part is so dense that it lost heat slower than the welder cooled down. Otherwise it would have been a losing race. Still, I managed to overheat the machine two more times before I finally got into the groove. I’d weld a few lines (about 3″ per line), then put the torch down to let it cool a bit and inspect my work. Eventually I got the timing right and didn’t have any problems after that.

The end result is that I welded up the ankle to a good degree. There are still some holes but instead of torturing the part with super high heat for another hour or two (which can weaken aluminum), I’ll eventually fill the remaining v-grooves with Lab Metal and then Rage Pro body filler (high end Bondo).

I’m going to grind down the welds and inspect them to make sure that I got good penetration into the v-grooves. I was using 3/32″ 4043 filler rod but suspect that many of my welds are just on the surface. If, after welding, this turns out to be the case then I’ll have to go back in and re-weld so that the part is strong enough and I don’t get stress cracks once it’s painted.

For the other ankle I’m going to preheat the part in the powder coating oven until it hits a 200 degree surface temp, then move it to the welding bay and start TIGging it immediately. Hopefully then the welder won’t shut down and I can get the welds done sooner and not torture the poor part.

I won’t grind the welds down until I get my super breathing mask in from Amazon. I figured $24 was a small price to pay for not inhaling aluminum dust.

After the ankles are done I’ll move on to the leg boxes, which look to be slightly easier (less heat-sink-ey since there’s less metal) as well as more harrowing since I haven’t been walked through the part by Keith. But I’m slowly gaining confidence and know what to look for. I might practice on some 1/4″ first, though, to see how it behaves. I’ll be right next to the edge the whole time and don’t want to blow an edge out. Oy.

I can say that the last 30+ hours has been tremendously educational, and Keith’s help was very, very appreciated. He wouldn’t take any money for helping me after I told him that I’d like to take R2 to a Children’s hospital. He just flat refused (he’s a softy). So I’m donating $50 in his name to the St. Jude’s Cancer Center via Baylor Tri Delta (that’s their sorority charity). I’m sure Keith will cry when I give him the card. 🙂

In the meantime, here are some pics from my work today. Pretty happy with progress, though it remains to be seen if those welds are deep enough.